Accurate Q-Factor Evaluation by Resonance Curve Area Method and Its Application to the Cavity Perturbation


IEICE TRANSACTIONS on Electronics   Vol.E77-C   No.6   pp.900-907
Publication Date: 1994/06/25
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Issue on Measurement Techniques for Microwave/Millimeter Wave)
resonance curve area method,  half power bandwidth method,  cavity perturbation,  accuracy improvement,  frequency dispersion of loss tangent,  

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An improvement of Q evaluation is discussed. The Resonance Curve Area method was confirmed to give a deviation in the order of 6104. The result was three times more accurate than the widely known Q evaluating method which utilizes the cursor function installed in a network analyzer. A discussion is also made on the physical validity of the RCA method. It is shown that the application of the RCA method improves the accuracy of the cavity perturbation method. Actual measurements have shown that the deviation of dielectric constant is less than 1% and that of the loss tangent is less than 3%, in the order of 104. The accuracy of the RCA method was estimated to be three times that of the conventional cavity perturbation technique. The consistency of the perturbation with other methods has also confirmed. The accuracy comparison to more accurate formulae derived from a rigorous solution have shown that the difference is sufficiently small.